How do you refactor?

Question

I was wondering how other developers begin refactoring. What is your first step? How this process (refactoring) differ if you refactor code which is not yours? Do you write

Answer 1

Start with getting unit tests, and then use automated refactoring tools. If the refactoring can't be automated then it's not truly a mechanical transformation of the code and so isn't a refactoring. The unit tests are to make sure that you are truly just performing mechanical transformations from one codebase to an equivalent one.